Overall Barcelona is the strongest team in La Liga this season with the most points scored compared to other teams. Barcelona is playing very charismatically under Hansi Flick's coaching and the title will be waiting at the end of the season. Even though Barcelona has beaten Real Madrid and Bayern Minich's in the Champions League, it is not certain optimistic about becoming La Liga champions in the coming season. Hansi Flick still has a long way to go in the league, he needs to be consistent in maintaining victory in every next match, I think Real Madrid will improve their statistics so they can catch up with Barcelona on points and will compete closely in the next match.
While Hansi Flick definitely is the main reason why they got this good, lets not forget to give Xavi credit for playing all these young players and getting them some time and helping them show their talents as well. For example, Lamine Yamal was already playing there before Flick, that dude became the starter at Barcelona at 16 years old when Xavi was there, in fact, thanks to that he was able to play for Spain at 16 as well.
So we need to remember, all these young talents that Hansi Flick could use? They came from the fact that Xavi didn't hesitated using La Masia. Of course that also ties to the fact that Barcelona has financial issues, and that meant they can't spend too much money on players, hence why they used their own youth players.